Device for optimization of the thickness of an ice layer

ABSTRACT

An ice resurfacing machine laser control is used to optimize the ice layer on an artificial ice track, such as an ice hockey rink and is adapted for use in ice resurfacing machines. The thickness of an ice layer is optimized with a beam for a laser transmitter. The ice resurfacing machine comprises a laser receiver and mechanisms to regulate the elevation of the scraper blade.

[0001] The invention relates to an ice resurfacing machine laser controlunit used for optimizing the thickness of the ice layer on an artificialice field, such as an ice hockey rink, whereby the elevation of the iceresurfacing machine's ice scraper blade is adjusted by controlling themovement of a regulating element, such as the movement of avariable-speed motor.

[0002] The number of ice rinks and ice arenas has grown quickly with thepopularity of ice hockey. In different countries, the estimated numberof ice rinks in which refrigeration machines are used to freeze the icefield is estimated to be 12,000 in total. In addition to these, openartificial ice fields are also used, but these are fewer in number.Nearly all ice rinks use ice resurfacing machines, which are used tomaintain, level and re-freeze the surface of the ice. In order to levelthe surface of the ice, the ice resurfacing machines have a scraper,which removes the worn surface of the ice and levels it. The scrapercomprises a blade which can be raised and lowered and which trims off alayer of a desired thickness of the Ice surface. In order to control theelevation of the blade, the resurfacing machines have either a manualelevation adjustment mechanism or a mechanized elevation adjustmentmechanism. The levelling of the ice surface has been completelydependent upon the skill of the operator of the ice resurfacing machine.For the levelling run of the machine, the thickness of the ice layer hasbeen measured, for example, by boring a hole into the ice.

[0003] Laser control units, transmitters and receivers have been usedfor very different measuring purposes. Their most common applicationscan be found in the field of structural engineering, in which lasermechanisms are used to determine a position of elevation. For example,laser measuring mechanisms are used for controlling earth movingmachines when making roads or the like. U.S. Pat. Nos. 4,273,196,5,375,663 and 5,917,593 illustrate a laser control unit installed on abulldozer, whereby the front bumper plate of the earth moving machine iscontrolled. Towed earth moving machines use the laser control unitsillustrated in U.S. Pat. Nos. 5,806,604 and 6,029,752. The use of lasermeasuring mechanisms in structural engineering of housing has alsobecome common.

[0004] The purpose of the invention is to provide a device foroptimizing the thickness of an ice layer, whereby the surface of the IceIs always levelled with the precision of a few millimeters as the wornice is being removed. When using a device according to the invention,there is no need to measure the thickness of the ice layer or to carryout different ice-levelling runs.

[0005] With the invention, variations in the thickness of the ice can becontrolled within an optimal margin of 15-25 millimeters. The accuracyof a laser control unit serves the purpose excellently. The icethickness in ice rinks varies significantly from one rink to another,within 15-80 millimeters. Ice maintenance has great significance on thevariations in the ice thickness. The utilization rate of an ice rink isgenerally nearly 100% and there is only time to level the ice at night,thus costs are great. About 2-3 working hours a week are used to levelthe Ice.

[0006] Ice is known to be a fair insulant. For this reason, thethickness of the ice has significant implications for the energyexpenditure of refrigeration machines. Measurements which have beencarried out have verified that the energy used for a 10-millimeter icelayer, over a working period of 8 months, is 6 MWh per year. Anadditional 50-millimeter ice layer increases the electricity bill byabout 30 MWh, which is equivalent to the amount of energy used annuallyby two electrically heated homes.

[0007] The previous disadvantages are eliminated and the previouslydefined objectives are accomplished with a device for optimizing thethickness of an ice layer according to the invention, thecharacteristics of which are defined in the characteristics section ofthe claims.

[0008] The most important advantage of the invention is the savingsattained in maintenance costs and energy when it is used. The time ittakes for a device for optimizing the thickness of an ice layeraccording to the invention to compensate for its own cost is less thanone working season. Other advantages include a level surface of ice andextended ice time as a result of a reduction in maintenance work. Areduction in energy consumption is also always an environmentallyfriendly solution. Additionally, the invention will facilitate the workof the ice maintenance personnel. The thickness of the ice affects thequality of the ice. Irregular freezing caused by deviations from theoptimum level of ice thickness is avoided and the ice field freezesevenly in connection with its maintenance.

[0009] Next, the invention will be described in detail with reference tothe accompanying figures.

[0010]FIG. 1 diagrammatically illustrates a side view of the lasercontrol unit and laser transmitter of a device for optimizing thethickness of an ice layer, which have been mounted on an ice resurfacingmachine.

[0011]FIG. 2 diagrammatically illustrates an enlarged side view of thelower part of the invention according to FIG. 1.

[0012]FIG. 3 diagrammatically illustrates a top view of the lasercontrol unit and the laser transmitter of a device for optimizing thethickness of an ice layer according to the invention.

[0013] An ice resurfacing machine laser control unit 1 according to theinvention is mounted advantageously to the back part of an iceresurfacing machine 2 as close to the Ice scraper 3 as possible, to itscenter section. In the method of implementation of the inventionillustrated in FIGS. 1-2, the tubular frame part 4 of the iceresurfacing machine laser control unit is mounted from its lower sectionto the cover of the ice scraper 3 and from its center section to thebody of the ice resurfacing machine 2. A free-sliding measuring rod 5has been fit vertically inside the upright tubular frame part 4, at thebottom end of which measuring rod, a runner 7, pressing on the icesurface 6 and reducing the surface pressure, measures the elevation ofthe ice surface 6.

[0014] The laser receiver 8 of the control unit 1 of the Ice machine ismounted on the top end of the measuring rod 5, which extends above thetop of the ice resurfacing machine 2. A laser transmitter 10, mounted ona tripod support 9, or the like, sends a laser beam 11, for examplerevolving or planar, the elevation of which is read with the scale 12 ofthe laser receiver 8. A signal which deviates from the measuring scale12 of the laser receiver 8 is conducted to the central unit 13, whichcontrols a variable-speed motor 14, or corresponding operating devicewhich regulates the elevation of the ice scraper 3 blade. A method ofimplementation of the invention in accordance with FIG. 1 includes avariable-speed motor 14, which has been equipped with a herringbone gearand which rotates the manually operated adjusting wheel 15 of the icescraper blade 3.

[0015] The extreme positions of the ice scraper 3 blade of the iceresurfacing machine 2 can be determined using sensors 16 and 17.Electric eyes, or the like, which function as sensors 16, 17, aremounted on the cover of the ice scraper 3 for manual adjustment. Theslide piece 18 moves on a horizontal plane, the elevation of the icescraper 3 blade changing. The minimal value of the blades removes thelayer of worn ice and the maximum values of the blades level the surfaceof the ice 6. The maximum blade value prevents the removal of a toothick ice layer. This way, the ice machine 2 accomplishes the work donein several levelling runs.

[0016] The laser control unit 1 of an ice resurfacing machine accordingto the invention is used in the following way, for example, for carryingout maintenance work on ice hockey rink 19. The support 9 of the lasertransmitter 10 is placed outside the borders of the ice hockey rink 19,such that the elevation of the beam 11 transmitted by the lasertransmitter 10 corresponds to the elevation of the laser receiver 8 onthe ice resurfacing machine 2. The support 9 is adjusted, such that thedistance of the laser beam 11 from the bedplate of the ice hockey rink19 is the same everywhere. In other words, the laser beam 11 is alignedparallel to the bedplate. The laser receiver 8 is mounted at the correctelevation on the end of the measuring rod 5 by considering the thicknessof the ice layer and the deviation from optimal thickness. The thicknessof the ice layer underneath the runners of the measuring rod 5 isdetermined, for example, by drilling a hole and then by setting thelaser receiver 8 at the right elevation.

[0017] An ice resurfacing machine 2 equipped with a laser control unit 1is used in maintenance work in the normal way and separate runs forlevelling the ice surface 6 are not necessary, because correction of theice surface 6 occurs as a continuous process. Once adjustments are seton the laser control unit 1 of the ice resurfacing machine, they do notneed to be changed, provided that the ice resurfacing machine is used onthe same ice field 19. Because the ice scraper 3 of the ice resurfacingmachine 2 cannot reach very close to the borders of the ice field 19,border ice is generally thinned with hand implements.

[0018] It is apparent to the professionals of the field that theinvention is not limited exclusively to the example described above, butthat it can vary within the frames of the claims presented below. Adevice for optimizing an ice layer according to the invention can beadapted to an ice resurfacing machine, for example, such that the laserreceiver 8 is located in a different place.

1. A device for optimization of the thickness of an ice layer used foradjusting the elevation of the ice scraper blade of an ice resurfacingmachine used for the maintenance of ice hockey rinks, or the like, whichhave been frozen with a refrigeration machine, or the like, which devicecomprises a laser transmitter, a laser receiver and regulating elementswherein there is arranged a measuring rod, or corresponding mechanism,which moves freely through a tubular frame part of a laser control unitof the ice machine, such that the bottom end of the mentioned measuringrod rests on the surface of the ice.
 2. A device for optimization of thethickness of an ice layer according to claim 1, wherein the laserreceiver is mounted to the top end of said measuring rod, orcorresponding mechanism, and that a variable speed motor, or the like,controlled by a beam transmitted by the laser transmitter and bydeviations measured by the laser receiver, is activated to adjust theelevation of the ice scraper blade of the ice machine.
 3. A device foroptimization of the thickness of an ice layer according to claim 2,wherein the measuring rod is fitted close to the ice scraper blade, toits center point.
 4. A device for optimization the thickness of an icelayer in according to claim
 3. wherein a runner, or the like, is mountedon the bottom end of the measuring rod for reducing the surface pressureexerted on the ice.
 5. A device for optimization of the thickness of anice layer according to claim 4, wherein the minimum and maximumpositions of the ice scraper blade are controlled by preset sensors,such as electric eyes or the like.
 6. A device for optimization of thethickness of an ice layer according to claim 5, wherein thevariable-speed motor is connected to a manually operated adjusting wheelof the ice scraper of the ice machine, to a cylinder or the like whichadjusts the elevation of the ice scraper blade.
 7. A device foroptimization of the thickness of an ice layer according to claim 6,wherein the laser transmitter is placed outside the ice hockey rink atan elevation which extends above the borders of the rink and above thetop of the body of the ice machine, above which the laser receiver hasbeen fitted.
 8. A device for optimization of the thickness of an icelayer according to claim 7, wherein the laser transmitter transmits abeam, which is either a revolving beam or a planar beam covering thewhole ice hockey rink, and parallel to the bed of the ice hockey field.9. A device for optimization of the thickness of an ice layer accordingto claim 1, wherein the measuring rod is fitted close to the ice scraperblade, to its center point.
 10. A device for optimization the thicknessof an ice layer in according to claim 1, wherein a runner is mounted ona bottom end of the measuring rod to reduce surface pressure exerted onthe ice.
 11. A device for optimization of the thickness of an ice layeraccording to claim 1, wherein minimum and maximum positions of the icescraper blade are controlled by preset sensors.
 12. A device foroptimization of the thickness of an ice layer according to claim 1,further comprising variable-speed motor connected to a manually operatedadjusting wheel of the ice scraper of the ice machine to adjust theelevation of the ice scraper blade.
 13. A device for optimization of thethickness of an ice layer according to claim 1, wherein the lasertransmitter is placed outside the ice hockey rink at an elevation whichextends above borders of the rink and above a top of the body of the icemachine above which the laser receiver is fitted.
 14. A device foroptimization of the thickness of an ice layer according to claim 1,wherein the laser transmitter transmits a beam, which is either arevolving beam or a planar beam covering the whole ice hockey rink, andparallel to a bed of the ice hockey field.